At present, during electromagnetic compatibility (EMC) immunity testing, at the emitting side, a signal generator, a high power RF amplifier, and a broadband antenna are used to generate a broadband RF field, typically in an EMC room such as an anechoic chamber or a Faraday cage. These systems most commonly are used in the frequency ranges of 30 MHz to 1 GHz, 1 GHz to 6 GHz and 1 GHz to 18 GHz. More generally, any range between 20 MHz and 40 GHz can be used. In such a system typically the high power RF amplifier is located outside the EMC room and the broadband antenna is located inside the room. Typically, the RF power is generated through combining a number of low power amplifiers, wherein significant power losses may occur as a result of the combiners. Also, further power losses occur in the cable connection between the power amplifier outside the EMC room and the broadband antenna inside the room.
At the receiving side, typically a broadband antenna in combination with a preselector is used, where the preselector normally is part of the measurement receiver. Such a broadband receiving antenna typically has a limited gain and directivity, whilst being large, complex and expensive. The preselector comprises a plurality of band pass filters to remove broadband noise and out-of-band signals, and may further comprise a built-in amplifier.